I. Field of the Invention
The present invention relates to a valve assembly. In particular, the present invention relates to a reed valve assembly for use with a motorcycle engine.
II. Description of Related Prior Art
A variety of lubrication systems for engines, such as, motorcycle engines, exist. Some of the systems relate to controlling the pressure differential between the crankcase, cam chest, and the rocker box to facilitate the return of oil from the rocker box to the crankcase. FIG. 1 illustrates a prior art motorcycle engine 11 incorporating one conventional valve assembly 17. The illustrated conventional valve assembly 17 is manufactured and sold by Harley-Davidson of Milwaukee, Wis. The engine 11 has an aperture 13 formed in a wall 15 between the crankcase and cam chest. The valve assembly 17 is positioned to cover the aperture 13 and is configured to permit one-way flow of air from the crankcase into the cam chest in response to pressure differentials caused by reciprocation of the engine's pistons.
As shown in FIGS. 2-4 the conventional valve assembly 17 includes a valve body 19 having at least one bore 27. The illustrated valve body 19 includes more than one bore 27. A flexible member 21 is secured to the valve body 19 by a fastener 23. The flexible member 21 is configured such that the circumference of the flexible member flexes away from the valve body 19 to open fluid communication through the bores 27; the flexure of the member 21 resulting from a pressure differential caused by reciprocation of the engine's pistons. In particular, the flexible member 21 opens or flexes away from the valve body 19 to provide fluid communication between the crankcase and cam chest when the pressure differential in the crankcase is greater than in the cam chest (represented by arrow A). The flexible member 21 closes or covers the bores 27 of the valve body 19 (as shown in FIG. 2) to prevent fluid communication through the bores 27 when the pressure differential in the cam chest is greater than in the crankcase (represented by arrow B).
Another conventional valve assembly is described in U.S. Pat. No. 6,457,449. Similar to the previously described arrangement, this valve assembly includes a valve body (116 of FIG. 5) having at least one bore (136). A flexible member (120) is secured to the valve body by a fastener (160). The valve assembly is positioned to cover an aperture (108 of FIG. 4) in a wall between the crankcase and cam chest, and is configured to permit one-way flow of air from the crankcase into the cam chest in response to pressure differentials caused by reciprocation of the engine's pistons.
In general, improvement has been sought with respect to such valve assemblies, generally to better accommodate: engine manufacturing efficiency and ease of retrofitting and improving engine performance. The present invention addresses such needs.